The present invention relates to vacuum cleaning apparatus and more particularly to wet/dry vacuum devices including a suction head supported on an open top collection tank.
Heretofore, various forms of wet/dry vacuum cleaning devices have been proposed. These devices basically include an open top collection tank and a suction head having a blower and being supported on the top of the tank. The blower creates a vacuum in the tank and draws debris and liquid into the tank through a hose connected to an inlet carried by the suction head or the collection tank. Float valve devices have been included in such apparatus to prevent ingestion of the liquid into the blower.
In order to empty the liquid contents from the collection tank, with some of these prior proposals, it has been necessary to remove the suction head and physically lift and tilt the tank. This procedure is tiring, time-consuming and the tank may be dropped spilling the contents on the floor. As a result, several proposals have been made to use the blower to pressurize the tank and thereby force the liquid contained therein out the tank inlet. An example of one such prior device may be found in U.S. Pat. No. 2,643,732 to Keen, entitled VACUUM CLEANING MACHINE, and issued on June 30, 1953. The device disclosed in this patent includes a cover disposed on a collection tank and supporting a motor-fan unit. The motor-fan unit includes a pressure discharge nozzle on one end and an intake nozzle on the other end. A hose communicates at one end through the cover with the tank and is connected at its other end either to the pressure discharge of the motor-fan unit or the intake nozzle thereof. When connected to the intake nozzle, a vacuum is created in the tank and liquid and other debris may be drawn therein. When connected to the pressure discharge unit of the motor-fan unit, the tank is pressurized and the liquid is forced up through a pipe and discharged through a tank inlet fitting.
Examples of prior wet/dry vacuum devices which permit selective evacuation or pressurization of a collection tank but which do not require shifting of a hose connection may be found in U.S. Pat. No. 3,331,090 to Reiber et al, entitled LIQUID SUCTION, STORAGE AND DISCHARGE DEVICE, issued July 18, 1967 and U.S. Pat. No. 3,605,786 to Machin, Jr. entitled EVACUATOR, issued on Sept. 20, 1971. Each of the devices disclosed in these patents includes a form of diverter or reversing valve for selectively pressurizing or evacuating the receptacle or collection tank. The device disclosed in Reiber et al includes a rotary, two-position, circular reversing valve having kidney-shaped passages selectively interconnecting the intake and discharge of an air blower with the collection tank. The device disclosed in Machin includes a fairly complexly configured ring-like valve operable to selectively evacuate or pressurize the collection tank.
All of these devices are complex and costly. A need exists for a structurally simple wet/dry vacuum cleaner including a reversing or diverter valve whereby problems heretofore experienced relating to complexity and difficulty of manufacture are substantially eliminated.